Fixed #35257 -- Corrected resolving output_field for IntegerField/DecimalField with NULL.

tests/expressions/tests.py

@@ -2654,6 +2654,29 @@ class CombinedExpressionTests(SimpleTestCase):
                 with self.assertRaisesMessage(FieldError, msg):
                     expr.output_field
 
+    def test_resolve_output_field_numbers_with_null(self):
+        test_values = [
+            (3.14159, None, FloatField),
+            (None, 3.14159, FloatField),
+            (None, 42, IntegerField),
+            (42, None, IntegerField),
+            (None, Decimal("3.14"), DecimalField),
+            (Decimal("3.14"), None, DecimalField),
+        ]
+        connectors = [
+            Combinable.ADD,
+            Combinable.SUB,
+            Combinable.MUL,
+            Combinable.DIV,
+            Combinable.MOD,
+            Combinable.POW,
+        ]
+        for lhs, rhs, expected_output_field in test_values:
+            for connector in connectors:
+                with self.subTest(lhs=lhs, connector=connector, rhs=rhs):
+                    expr = CombinedExpression(Value(lhs), connector, Value(rhs))
+                    self.assertIsInstance(expr.output_field, expected_output_field)
+
     def test_resolve_output_field_dates(self):
         tests = [
             # Add - same type.